"It looks like, when you go into it, there's a whole lot of pros and cons, and there's a 50-50 argument," he said.

In reality, almost 100 per cent of doctors are pro-vaccine.

The Australian Vaccination Network sounds like an organisation that would agree with Mr Williams' views that vaccination is a life saver, but it does not.

In fact, it actively promotes the link between vaccination and autism, a theory that was debunked by the medical world 20 years ago.

The NSW Department of Fair Trading has ordered it to change its name, but the AVN is resisting the order in court.

The parties will be back in court on Friday.

New South Wales Opposition health spokesman and paediatrician, Dr Andrew McDonald, says the AVN's name is a serious problem.

"This is all about false advertising. The Australian Vaccination Network, a vehement anti-vaccination group, who are doing whatever they can to keep their name near the top of a Google search," he said.

"They're number two on a Google search if you use the words 'Australia' and 'vaccination' and that's why they want to preserve their name to keep it there."

AVN accused of attacking pro-vaccine campaigners

Journalist Jane Hansen has been heading up a recent campaign at Sydney's Sunday Telegraph designed to raise vaccination rates.

"Anyone who criticises the AVN - and this is journalists, politicians or even parents that have had sick children who have gone public with their views on vaccination - very quickly find themselves on the end of some pretty vile attacks," she said.

"They pride themselves on this all natural approach but there's no peace, love and lentils if you criticise them.

"They come at you, criticising you of being on the payroll of 'Big Pharma'."